If the internet survives the SOPA menace, it will be on its way to its biggest transition in decades on June 6, 2012. That's World IPv6 Launch Day, a day where many of the internet’s largest sites will switch over to the new 128-bit address scheme.

Currently IP addresses use 32 bits, which works out to about 4.3 billion unique addresses. To combat the growing address shortage, network firms developed network address translation (NAT) techniques, which simply reassigned addresses on a local network to internal IPs and routed packets accordingly. The new limit thus became 4.3 billion unique gateways to the main internet, as local networks would not have enough machines to run out of IP addresses.

Still the problem remained so the in the late 1990s the Internet Engineering Task Force (IETF) set to work making the replacement to IPv4 -- 32-bit IP addresses. In 1998 they published RFC 2460, the 128-bit standard that would come to be known as IPv6.

[Image Source: Boot Click]

By 2008, though, few had adopted the solution with less than 1 percent of internet traffic going through IPv6.

But necessity is the mother of invention and Google Inc. (GOOG) is championing the IPv6 cause. IPv6 engineer Erik Kline writes:

Just a year ago, we announced our participation in World IPv6 Day. Since then, the IPv4 address global free pool was officially depleted, each of the five regions around the world receiving one last address block. Soon after, the Asia-Pacific region exhausted its free IPv4 address pool. Hundreds of websites around the world turned on IPv6 for a 24-hour test flight last June. This time, IPv6 will stay on.

For Google, World IPv6 Launch means that virtually all our services, including Search, Gmail, YouTube and many more, will be available to the world over IPv6 permanently. Previously, only participants in the Google over IPv6 program (several hundred thousand users, including almost all Google employees [PDF]) have been using it every day. Now we’re including everyone.

Google is urging its users to go to ipv6test.google.com to test compatibility, as a handful of ISPs are believed to not be ready for IPv6.

While the UFC appears ready to go full-blast with IPv6, adoption plans in the developing world and other regions are much less developed. It may take several years before the transition is full complete.

One misconception about IPv6 is that it will make you easier to identify or track. While it will show the world your full address (local+gateway), companies could still opt to use NAT to maintain private single address networks. And you could still use NAT to obfuscate or otherwise mask your true IPv6 address. And of course all of the fears overlook the simple fact that whether it's a local or a global IP address, that an IP address cannot identify a person explicitly as there can be multiple users and/or multiple machines.